1895.] LOitlUS PLATOPALI/IATUS AlfD PSITTACUS EBITHACUS. 371 



piece which bears the ascending median ridge and the two concavities 

 on either side of it. Towards the dorsal end of each lateral 

 margin is a short but sharp dorsal process (djy), so that a notch is 

 formed on either side of the uppermost part of the median ossifi- 

 cation just before it merges into the horizontal osseous bar which 

 forms the dorsum of the hinder aspect of the prosopium. 



In Lorius JlavopalUatus the posterior surface of the prosopium is 

 relatively as well as actually much less dorso-ventrally extended ; 

 the posterior nares are more nearly horizontal and much less 

 inclined ventrad externally ; the lachrymal processes are shorter 

 and especially less produced dorsad, and the lateral processes are 

 larger (instead of smaller) than the median ones, and descend 

 ventrad much beyond (instead of much less than) the median ones. 



II. The Cranium. 



The lateral aspect of the cranium (see figs. 1 & 2) shows — in 

 addition to what has been said as to the lateral aspect of the skull 

 as a whole — the following characters. At the dorsal part of its pre- 

 axial margin the nasal process of the frontal (np) is less conspicuous 

 in L.JJavopalliatus than in P. erithuciis. Of the margin of the inter- 

 orbital septum its dorsal part does not form so marked an angle with 

 the ventral part of it in front of the attachment of the palatines. 

 The preaxial end of the zygoma is less dorso-ventrally expanded. 

 The preaxial margin of the palatine is slightly less, aud its ventral 

 margin rather more, concave. The postero-inferior angle is larger 

 and more prominent, while instead of the more or less long post- 

 axial process (pp), which in P. erithacus projects dorsad and 

 postaxiad from the summit of the postaxial margin of the palatine, 

 there is an exceedingly small one which does not project as much 

 as does the ventral boundary of the postaxial concavity of the 

 bone. The external surface of the palatine is also more concave 

 dorso-ventrally, especially in its hinder half. 



Of the dorsal margin of the palatine the part joining the basis 

 cranii is about as long, relatively, as in P. erithacus, but the part of 

 that margin postaxial to that junction develops two processes 

 towards its postaxial termination. 



The orbit is almost bounded infero-externally by bone, the 

 lachrymal extending postaxiad to within a short distance of the 

 sphenotic process (sjyh). Posteriorly, however, the orbit is less 

 encircled by bone at its outer margin, for the postorbital process 

 (po) is very much shorter, not projecting at all downwards, and 

 relatively not so much outwards as in P. erithacus. 



The sphenotic process is also relatively somewhat shorter and 

 notably different in shape, and it does not descend, as in 

 P. erithacus, almost to the dorsal margin of the zygoma. 



In the latter species it projects forwards and downwards and 

 also a little outwards. It is flattened dorsally and externally, and 

 is longitudinally channelled on its ventral surface, the inner margin 

 of that channel being prolonged into a short pointed process, 



24* 



